After I cum with a girl about twice, I need to think of sucking cock and getting covered in cum to get hard again but initially I can do it jus with her....
Nah, that's not weird. I think it's normal to need a little more stimulation - mental or physical - the second time. I can get off thinking about lots of stuff, but when it's not happening for whatever reason, I have a few go-to fantasies that will usually do the trick.